Large diameter sampler for gathering an undisturbed sample

ABSTRACT

A large diameter sampler for gathering an undisturbed sample includes an outer tube provided with a bit on a bottom portion thereof for excavating a ground, wherein the outer tube is rotated by applying an outer power for penetrating into the ground; unit for protecting a sample from a disturbance generated by a rotating excavation of the bit, wherein the protecting unit is located the bottom portion of the outer tube, internally, and is penetrated into the ground by weight; a sampling tube for locating the sample pulled-out by self-gravity of the protecting unit; a cutting unit for sheltering a bottom portion of the sampling tube for protecting spilling of the gathered sample, wherein the cutting unit is equipped within the protecting unit and cutting the sample pulled-out by the sample protecting unit; unit for up-lifting the sampling tube and the protecting unit by applying an up-lift force from an operating device which is located on the ground; and an outer rod for connecting the outer tube and a boring device on the ground.

FIELD OF THE INVENTION

[0001] The present invention relates to an large diameter sampler; and, more, particularly, to an large diameter sampler capable of gathering undisturbed sample in a cohesive soil as well as a sandy soil in ground of a investigation for examining a subsoil, a soil, a groundwater level, an internal force of a ground and a barrier situation within a plateau.

DESCRIPTION OF THE PRIOR ART

[0002] Recently, with rapid improvement of industry and development of a whole country, a construction for a civil engineering, a building and an environmental facility may be no more carried out in a favorable condition site.

[0003] That is, even in unfavorable places, such as a seaside, a mountainous area, a sanitary landfill and nearby of a constructed facility, etc., which are excluded in past, the construction may be proceeded.

[0004] With this, for a safe and economical design and execution of a structure, and for repairing and maintaining of an established structure, ground information and analysis through an accurate ground investigation is required.

[0005] The ground investigation is aimed at providing basic materials, such as ground characteristics, soil conditions and an amount of ground settlement calculation.

[0006] Especially, when designing a structure, it is important to regulate ground settlement caused by a structure load within a permitted level, and the load given to a foundation may not over the allowable bearing capacity. Therefore, all information, which may affect safety of a structure and a material needed in calculating ground settlement may be acquired through a ground investigation.

[0007] Also, the ground investigation may be carried out delicately and before the construction for determining a structure, kinds of foundation, a construction method and building materials. If the ground investigation is delayed, it may not be carried out delicately due to a fixed construction period, and it may be impossible to find an economical solution.

[0008] The ground investigation costs just 1˜2% of total cost, however, saving of the costs may damage the whole construction.

[0009] In advanced countries, many investment and researches are going on to invent a sampler, which gathers undisturbed sample in a soft foundation because soil parameters are changed according to a sampler. There is a research results that a sample gathered by a large diameter Laval sampler made by Laval University, in Canada, has small disturbance than that of Japanese gathered by a piston sampler.

[0010] However, in a domestic soft foundation site, a water pressure type piston sampler is mostly used to gather an undisturbed sample and a sandy soil is not gathered yet.

SUMMARY OF THE INVENTION

[0011] It is, therefore, an object of the present invention to provide a large diameter sampler capable of gathering an undisturbed sample in a cohesive soil as well as a sandy soil for more accurately acquiring a soil parameter which is needed foundation design of a structure.

[0012] It is, therefore, another object of the present invention to provide a large diameter sampler capable of gathering an undisturbed sample and lifting an un-cohesive sample up to the ground without spilling by equipping a cutter having cutting and sample spilling interception function within a sampling tube.

[0013] In accordance with an aspect of the present invention, there is provided a large diameter sampler for gathering an undisturbed sample, comprising: an outer tube provided with a bit on a bottom portion thereof for excavating a ground, wherein the outer tube is rotated by applying an outer power for penetrating into the ground; means for protecting a sample from a disturbance generated by a rotating excavation of the bit, wherein the protecting means is located the bottom portion of the outer tube, internally, and is penetrated into the ground by weight; a sampling tube for locating the sample pulled-out by weight of the protecting means; a cutting means for sheltering a bottom portion of the sapling tube for protecting spilling of the gathered sample, wherein the cutting means is equipped within the protecting means and cutting the sample pulled-out by the sample protecting means; means for up-lifting the sampling tube and the protecting means by applying an up-lift force from an operating device which is located on the earth; and an outer rod for connecting the outer tube and a boring device on the earth.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Other objects and aspects of the invention will become apparent from the following description of the embodiments with reference to the accompanying drawings, in which:

[0015]FIG. 1 is a cross-sectional view illustrating an large diameter sampler capable of gathering an undisturbed sample in accordance with the present invention;

[0016]FIG. 2 is a cross-sectional view showing a cutting part configuration of a large diameter sampler in accordance with the present invention;

[0017]FIG. 3 is a cross-sectional view showing a head part configuration of a large diameter sampler in accordance with the present invention;

[0018]FIG. 4 is a perspective view showing a sectional configuration of a lumbar of a large diameter sampler in accordance with the present invention;

[0019]FIGS. 5A to 5E are situational views showing a cutting part configuration in accordance with the present invention; and

[0020]FIGS. 6A and 6B are cross-sectional views showing ground excavation ground by relatively giving interval between a bit and a shoe in condition to the ground with the spring functions, and protecting a sample from a disturbance generated by the excavation in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, a large diameter sampler according to the present invention will be described in detail referring to the accompanying drawings.

[0022] A large diameter sampler in accordance with the present invention is capable of gathering undisturbed sample in a cohesive soil as well as a sandy soil.

[0023] Referring to FIGS. 1 to 3, the sampler includes an outer tube 1 which provides a bit 2 in its bottom portion for excavating a ground, wherein the outer tube 1 rotates by applying an outer power for penetrating into the ground. A shoe 3 protects a sample from a disturbance generated by a rotating excavation of the bit 2, wherein the shoe 3 is internally equipped to a bottom portion of the outer tube 1, and penetrated into a ground with weight.

[0024] An extension tube 4 connects inside of the shoe 3 and a sampling head, and is extracted by the penetrating of the shoe 3. A sampling tube 5 is inserted within the extension tube 4 and puts in the sample gathered by the shoe 3.

[0025] A sampling head 6 is equipped to a top portion of the sampling tube 5 and outputs slime existed on the sample. A cutter 7 is equipped within the shoe 3 and cuts a sample pulled-out by its weight, and prohibits an outputting of the gathered sample. A guide tube 8 is engaged within the cutter 7 and prohibits disturbance of the gathered sample caused by the cutter 7. A cutting rod 9 is vertically equipped outside of the shoe 3, and elevates in condition of internally fitting the shoe 3. A cutting ring 10 is equipped to a bottom portion of the shoe 3 and connects the cutting rod 9 and the cutter 7.

[0026] An inner rod 11 inserts its one side into the sampling head 6 and connects its the other side into an operating device on the ground.

[0027] An outer rod 12 connects the outer tube 1 and a boring device (not shown), and a bearing 13 is externally equipped to the inner rod 11, to smoothly rotate the outer tube 1 and prohibits rotation of the shoe 3 connected to the sampling tube 5.

[0028] Finally, a spring 14 regulates the sample gathered by the rotating excavation of the bit 2, through an elastic operation to have relative gap between the bit 2 of the outer tube and the shoe 3, according to ground intensity.

[0029] In here, the extension tube 4 has a predetermined diameter of round unit 4A in its bottom portion and the cutter 7 formed in a pentagon on its top portion as shown in FIG. 4 and equipped outside of the cutting ring 10 by folding in predetermined part, and the cutter 7 and the cutting ring 10 are fixed with a connection part 22, such as a bolt.

[0030] As shown in FIG. 5A, the cutter 7 is located between the guide tube 8 and the extension tube 4 by fixing the cutting ring 10. When the inner rod 11 is pulled by the ground as shown in FIGS. 5B and 5C, top unit of the cutter 7, that is the top unit formed in pentagon, is drawn out inside of the sampling tube 5 with guidance of the round unit 4A of the extension tube 4, to thereby folded each other and closed in the form of camera closing, as shown in FIGS. 5D and 5E.

[0031] As shown in FIGS. 6A and 6B, then shoe 3 is projected at a predetermined length than an end edge of the bit 2. The length different gives relative interval between the bit 2 and the shoe 3 in excavation in condition to the ground with the spring 14 functions.

[0032] That is, in a soft ground, by an electricity of the spring 14, the interval between the bit 2 and the shoe 3 is increased. Also, in a hard ground, such as bedrock, the interval between the bit 2 and the shoe 3 is decreased, by a compression of the spring 14, and thereby processing an excavation.

[0033] Likewise, a disturbance caused by the excavation of the bit 2 is intercepted by the shoe 3, to thereby protect the gathered sample.

[0034] The operating process of the present invention will be described.

[0035] As shown in the drawings, to gather an undisturbed sample of a cohesive soil or a sandy soil, first, the bit 2 of the outer tube 1 is equipped on the ground.

[0036] Subsequently, by applying a rotating power to the outer tube 1, then the bit 2 excavates the ground and penetrates into the ground. At this time, the shoe 3, which is more extruded than the end edge of the bit 2 is penetrated into the ground by weight. The shoe 3 cuts off a disturbance soil generated by the penetrating of the bit 2, to thereby prohibit disturbance of the inserted sample.

[0037] Also, when the shoe 3 is penetrated, the sampling tube 5 is penetrated too, through extracting of the extraction tube 4.

[0038] When the required samples are gathered into the sampling tube 5, then the inner rod 11 is lifted. In this course, the tip of the cutter 7, which is located in a hole between the extension tube 4 and the guide tube 8 is draw out along to the hole to cut off the sample and close the bottom portion of the sampling tube 5, thereby preventing spilling of the sample.

[0039] As above described, by gathering an undisturbed sample into the sampling tube 5, a soil parameter needed in foundation design of a structure can be obtained more accurately.

[0040] In here, the soil parameter means unity of a cohesion, an angle of internal friction, a stiffness, a compression index and a coefficient of consolidation, and is needed in foundation of a structure, a bridge and a retaining wall.

[0041] As above described, when gathering a cohesive soil or a sandy soil, the large diameter sampler in accordance with the present invention protects the samples, which may be disturbed in the course of excavating, by using a shoe, and provides a cutter which cuts off the sample and closes a bottom portion of a sampling tube, to thereby easily gathers an undisturbed sample and accurately obtains a soil parameter needed in foundation design of a structure.

[0042] Although the preferred embodiments of the invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. 

What is claimed is:
 1. A large diameter sampler for gathering an undisturbed sample, comprising; an outer tube provided with a bit on a bottom portion thereof for excavating a ground, wherein the outer tube is rotated by applying an outer power for penetrating into the ground; means for protecting a sample from a disturbance generated by a rotating excavation of the bit, wherein the protecting means is located the bottom portion of the outer tube, internally, and is penetrated into the ground by weight; a sampling tube for locating the sample pulled-out by weight of the protecting means; a cutting means for sheltering a bottom portion of the sampling tube for protecting spilling of the gathered sample, wherein the cutting means is equipped within the protecting means and cutting the sample pulled-out by the sample protecting means; means for up-lifting the sampling tube and the protecting means by applying an up-lift force from an operating device which is located on the earth; and an outer rod for connecting the outer tube and a boring device on the earth.
 2. The large diameter sampler of claim 1 , wherein the protecting means forms a cylindrical shoe with a sharp angle at a bottom portion thereof.
 3. The large diameter sampler of claim 1 , further includes: an extension tube which is internally equipped within the protecting means and flexibly operating when it is penetrated into a ground by its weight; and a guide tube which is internally equipped within the cutting means and protecting disturbance of the gathered sample.
 4. The large diameter sampler of claim 3 , wherein the extension tube forms predetermined diameter of round unit in its bottom portion.
 5. The large diameter sampler of claim 1 , wherein the cutting means includes: a cutting ring located in a bottom portion of the protecting means in a cylindrical form; a cutter which equipped its bottom portion in an outside of the cutting ring, and according to the uplifting operation of the uplifting means, it's tip is draw out in a way or camera shutter closing by guiding of a round unit of the extension tube then closing the bottom portion of the sample protecting means; and a connection means for fixing the cutter on the cutting ring.
 6. The large diameter sampler of claim 2 , wherein the cutting means includes: a cutting ring located in a bottom portion of the protecting means in a cylindrical form; a cutter which equipped its bottom portion in an outside of the cutting ring and according to the uplifting operation of the uplifting means, it's tip is draw out in a way or camera shutter closing by guiding or a round unit of the extension tube then closing the bottom portion of the sample protecting means; and a connection means for fixing the cutter on the cutting ring.
 7. The large diameter sampler of claim 3 , wherein the cutting means includes: a cutting ring located in a bottom portion of the protecting means in a cylindrical form; a cutter which equipped its bottom portion in an outside of the cutting ring and according to the uplifting operation of the uplifting means, it's tip is draw out in a way or camera shutter closing by guiding of a round unit of the extension tube then closing the bottom portion of the sample protecting means; and a connection means for fixing the cutter on the cutting ring.
 8. The large diameter sampler of claim 4 , wherein the cutting means includes: a cutting ring located in a bottom portion of the protecting means in a cylindrical form; a cutter which equipped its bottom portion in an outside of the cutting ring and according to the uplifting operation of the uplifting means, it's tip is draw out in a way or camera shutter closing by guiding of a round unit of the extension tube then closing the bottom portion of the sample protecting means; and a connection means for fixing the cutter on the cutting ring.
 9. The large diameter sampler of claim 5 , wherein the cutter has a sharp end edge and equipped to the cutting ring by folding in a predetermined gap.
 10. The large diameter sampler of claim 6 , wherein the cutting means includes: a cutting ring located in a bottom portion of the protecting means in a cylindrical form; a cutter which equipped its bottom portion in an outside of the cutting ring and according to the uplifting operation of the uplifting means, it's tip is draw out in a way or camera shutter closing by guiding of a round unit of the extension tube then closing the bottom portion of the sample protecting means; and a connection means for fixing the cutter on the cutting ring.
 11. The large diameter sampler of claim 7 , wherein the cutting means includes: a cutting ring located in a bottom portion of the protecting means in a cylindrical form; a cutter which equipped its bottom portion in an outside of the cutting ring and according to the uplifting operation of the uplifting means, it's tip is draw out in a way or camera shutter closing by guiding of a round unit of the extension tube then closing the bottom portion of the sample protecting means; and a connection means for fixing the cutter on the cutting ring.
 12. The large diameter sampler of claim 8 , wherein the cutting means includes: a cutting ring located in a bottom portion of the protecting means in a cylindrical form; a cutter which equipped its bottom portion in an outside of the cutting ring and according to the uplifting operation of the uplifting means, it's tip is draw out in a way or camera shutter closing by guiding of a round unit of the extension tube then closing the bottom portion of the sample protecting means; and a connection means for fixing the cutter on the cutting ring.
 13. The large diameter sampler of claim 1 , wherein the uplifting means includes: a cutting rod vertically established outside of the sample protecting means; and an inner rod connects its one side and the other side into the sampling tube and the cutting rod, respectively, and provided with an uplift force from a ground device.
 14. The large diameter sampler of claim 1 , further includes a sampling head which is equipped top portion of the sampling tube and drawn off a slime existed on the sample.
 15. The large diameter sampler of claim 9 , further includes: a bearing which is externally equipped to the inner rod and smoothly rotates the outer tube and prevents rotation of the shoe connected to the sampling tube; and a spring which is elastically operating for having a relative gap between the bit of the outer tube and the shoe, according to the ground intensity, and regulating the sample gathered by rotating excavation of the bit is not disturbed.
 16. A cutting apparatus for use in a sampler, comprising: a cutting ring located in a bottom portion of the protecting means in a cylindrical form; a cutter which equipped its bottom portion in an outside of the cutting ring and according to the falling operation of the uplifting means, it's tip is draw out in a way or camera shutter closing by guiding of a round unit of the extension tube then closing the bottom portion of the sample protecting means; and a connection means for fixing the cutter on the cutting ring.
 17. The cutting apparatus of claim 16 , wherein the cutter has a sharp end edge and equipped to the cutting ring by folding in a predetermined gap. 